Drying apparatus



Inv e n Tor. Hermann Home ATTys.

H. HAAsv DRYING APPARATUS Filed Feb. 27, 1931 Flg. l.

March 13, 1934.

Patented Mar. 13, 1934 19,950,942 A" DRYING APPARATUS Hermann Haas,Lennep, Germany Application' February 27, 1931, serial no. 518,619

In Germany March 11, 1930 42 claims. (C1. 34-19) This invention relatesto a continuous drying apparatus of that type which comprises a dryline2 2, Fig. 1;

ing chamber divided into a plurality of 'communicating sections throughwhich the material to be dried passes progressively, and which is alsoprovided with means for establishing a local circulation of the dryingmedium through each section as well 'as a progressive movement of thedrying medium through the chamber from one end to the other.

In prior drying apparatus of this type it has been customary to providemeans for heating locally the drying medium which is circulated througheach section of the drier.

The present' invention has for its, object to provide a drying apparatusof thisv general -type in which the drying medium which is being locallycirculated in `the separate sections is heated from a central or commonheating apparatus that may be, located at a greater or less distancefrom the dryingv chamber. Thedrying medium which is thus heated at thecentral of the .drier and thecorresponding circulating passage H.- c

In accordance with the presentdnvention the heated air which is utilizedfor drying the material in the drying chamber 1 is furnished from an airheater L that is common to all of the Vsections A, B, C, D, etc..of thedrying chamber.

heating-station is distributedto the different.

sections of the drier in the proportions'needed to maintain the desiredtemperature and drying conditions in each section.

In the accompanying drawlng wherein I have.

illustrated a selected embodimentof my. invention, Fig. 1 is a side viewof a drier embodying my invention; Fig. 2 is a sectional view onsubstantially the Fig.. 3 is a section on the line 3--3, Fig. 2.

In the drawing 1 indicates the drying chamber which is herein shown asdi ided to uform a plurality of sections A, B, C, D, `,`etc. which areconnected to each other The material to be dried is passed progressivelythrough the `:on-

lleading to the lower portion of each of the cir- This air heater L mayhave any suitable or usual construction. It is shown as havingassociated therewitha fan or blower V by which air `is supplied to theheater for being heated and said heater is also provided with adischarge pipe R provided with branches 8, one branch culating passagesH. YEach branch 8 is provided with a valve by which the amount of heatedair delivered throughthe branch may be regulated, these valves beingindicated at S1, S2, S3,

G indicates an aspirator or suction device which is connected to theentering end of the drying chamber 1. At the other end the dryingchamber 1 is provided with an inlet opening O which leads into the lastsection E. The operation of the suction device G is to cause a gradualmovement ofthe air through the drier from the delivery`end to theentering end.

Y If desired, the air which is fed to the heater L by the blower V maybe taken from thesection E through the medium of a pipe connection Inthe operation of the device the blowers 5 will create a localcirculation of air in each section ofthe drying chamber and through theoperation of the heater L and blower V hot air will be supplied throughthe branch pipes 8 to rthe various'sections of' the drier, such hot airnecting sections, said material 'entering the section A at the left handend and'progressing through the various sections and being dischargedirom the right hand end of section E.

Associated with each section of the drier and situated at one sidethereof is a circulating passage H Which is separated from the dryingchamber by a partition 2.

Each circulating passage H, communicates' with the drying chamberthroughtwo openings 3 and 4 that are formed in the partition 2, theopening 3 being at the upper part 4of the partitionand the opening 4 atthe lower part thereof. i

5 indicates a fan or air-forcing, device which operates to create alocal circulation, indicated by the arrows 6, Fig. 3, through eachvsectibn commingling with and forming part of the local 1 circulation ineach section indicated by the ar- 'A rows,6. 95 f By regulating thevalves S1, 'SZ, S3, S4, etc. the amount of hot air which is deliveredto-each A section can be adjusted so as to maintain in each section A,B, C, D the desired drying conditions. The suction device G willmaintain a progressive circulation of air from the section E through thevvarious sections to and through the section A.

By providing a single air-heating device for all of the various sectionsof the drier it is possible to locate this heating device at a greateror less distance from the drying chamber and also to use heat'whichwould otherwise go to waste for heating the air.

I claim:

1. A drying apparatus comprising a drying chamber through which thematerial to be dried passes from one end to the other and which isdivided into a plurality of communicating sections, a circulatingpassage for each section, each circulating passage communicating withthe drying space of its section at both the top and the the bottomthereof, a valve in each branch, and.

means independent of the fans for delivering heated air from the airheater into said circulating passages through the branches of saidconduit.

2.1"A drying apparatus comprising a housing enclosing a drying chamberthrough which the` material to be dried passes from one end to the otherand which is divided into a plurality of communicating sections,vertical partitions forming within said housing circulating passages,one for each section, each. circulating passage having a dimensionlengthwise of said housing equal to the corresponding dimension of thecorresponding section and extending from the top-to the bottom of thehousing, and communicating with the drying space of its section at bothsaid top and bottom thereof, a fan in each circulating passage at thebottom thereof for producing a local circulation through said passageand the Acorresponding section of the drying chamber,

means for producing a progressivecirculation from the discharge end ofthe drying chamber to the entering end, an air heater common to all ofthe sections of the drying chamber but separate from and locatedexterior thereto, a conduit leading from said air heater and providedwith branches, one leading into each circulating passage at the bottomthereof adjacent one end, and means independent of the fans forwithdrawing air from the delivery end of the drying chamber and passingit through the air heater and into said conduit and through said.branches into the circulating passages and a valve in each branch tocontrol the ow of heated air therethrough. f

` HERMANN HAAS.

